Mal3 CH domain homology model and mammalian tubulin (2XRP) docked into the 8.6-Angstrom cryo-EM map of Mal3-GTPgammaS-microtubulesMal3 CH domain homology model and mammalian tubulin (2XRP) docked into the 8.6-Angstrom cryo-EM map of Mal3-GTPgammaS-microtubules

Structural highlights

4abo is a 9 chain structure with sequence from Cbs 356 and Sus scrofa. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:,
Activity:Tubulin GTPase, with EC number 3.6.5.6
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[MAL3_SCHPO] May play a role in regulating the integrity of microtubules possibly by influencing their stability. Involved in an anchoring mechanism to maintain tea2 and tip1 at growing microtubule ends. Strongly stimulates the ATPase activity of tea2.[1] [2]

Publication Abstract from PubMed

Growing microtubule ends serve as transient binding platforms for essential proteins that regulate microtubule dynamics and their interactions with cellular substructures. End-binding proteins (EBs) autonomously recognize an extended region at growing microtubule ends with unknown structural characteristics and then recruit other factors to the dynamic end structure. Using cryo-electron microscopy, subnanometer single-particle reconstruction, and fluorescence imaging, we present a pseudoatomic model of how the calponin homology (CH) domain of the fission yeast EB Mal3 binds to the end regions of growing microtubules. The Mal3 CH domain bridges protofilaments except at the microtubule seam. By binding close to the exchangeable GTP-binding site, the CH domain is ideally positioned to sense the microtubule's nucleotide state. The same microtubule-end region is also a stabilizing structural cap protecting the microtubule from depolymerization. This insight supports a common structural link between two important biological phenomena, microtubule dynamic instability and end tracking.

EBs recognize a nucleotide-dependent structural cap at growing microtubule ends.,Maurer SP, Fourniol FJ, Bohner G, Moores CA, Surrey T Cell. 2012 Apr 13;149(2):371-82. PMID:22500803[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Busch KE, Hayles J, Nurse P, Brunner D. Tea2p kinesin is involved in spatial microtubule organization by transporting tip1p on microtubules. Dev Cell. 2004 Jun;6(6):831-43. PMID:15177031 doi:http://dx.doi.org/10.1016/j.devcel.2004.05.008
  2. Browning H, Hackney DD. The EB1 homolog Mal3 stimulates the ATPase of the kinesin Tea2 by recruiting it to the microtubule. J Biol Chem. 2005 Apr 1;280(13):12299-304. Epub 2005 Jan 23. PMID:15665379 doi:http://dx.doi.org/10.1074/jbc.M413620200
  3. Maurer SP, Fourniol FJ, Bohner G, Moores CA, Surrey T. EBs recognize a nucleotide-dependent structural cap at growing microtubule ends. Cell. 2012 Apr 13;149(2):371-82. PMID:22500803 doi:10.1016/j.cell.2012.02.049

4abo, resolution 8.60Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA